1E1D-EC is a one span,selectable E1 or T1 pci card ,suitable for asterisk/freeswitch based applications, works with Seamless connection to Elastix ,trixbox and goautodial,etc. 1E1D-EC supports industry standard telephony and data protocols, like pri(Primary Rate ISDN, used in American and Standard Euro),ss7 and R2. 1E1D-EC is suitable for the voip usage including Traditional Calls/VoIP Calls Conference, Call Center,IVR System,Callback Service,PBX to PBX trunking, gateway,ippbx, etc. 1E1D-EC takes full dvantage of Octasic Hardware Echo Cancellation Module to deliver superior voice quality over T1/E1 interface. without hardware echo cancel module ,the echo cancel had to be achieved by mg2 oslec software ,it will cost a lot of resource of cpu ,even though, the effect of software echo cancel is much less than hardware echo cancel. 1E1D-EC use dahdi driver wct4xxp, no other driver need ,dahdi and asterisk are all open source software ,it can download from web site. Using 1E1D-EC plus dahdi and asterisk, you can setup your telephoney system or pbx quickly, save the cost for software. If you met any problem when using 1E1D-EC card, we provide technical support by email or teamviewer or ssh. 2 Year Warranty.